Design and Build Quality

Audio-Technica M40X and Audio-Technica M50x come with a quarter inch adapter, a 3-meter cable, and a coiled cable. However, the M50x comes with an extra 1.5-meter straight cable.

Unlike the older M series headphones, the cables are now removable in both of them adding to the overall build quality and longevity of these headphones.

However, you do also need to note that you are allowed to use only the Audio-Technica cables.

Sadly, You cannot use any other cables.

These headphones also come with a leather bag that is great for portability. The headphones can easily be folded and stored inside the bag.

Also, these two devices are mostly similar. However, the M50x is little larger and heavier. The M40x feels lighter on the end.

However, you’ll notice this only if you have both of these headphones in hand.

In short.

The build quality wise, both of these headphones are great.

The M50x build quality is slightly better as the earcups feel premium. Design wise these two are very similar.

Sound Quality

As these are monitoring closed-back headphones, the audio sounds more natural.

The relatively flat frequency response these headphones have got to offer is ideal for studio monitoring purposes.

The M50x headphones have a slightly larger driver at 45mm.

Whereas, the M40x has a smaller driver at 40mm.

​The bass is controlled in both of them so that they won’t leak to the mids. The bass is not heavy so that it is ideal for monitoring purposes.

There’s a slight emphasis on the bass part of the M50x, whereas M40x is for you if you love flat sound.

So, I can say that the bass is slightly more prominent in M50x than M40x.

But they’re not bass-heavy.

If you are an audiophile, you can easily notice the slightly richer sound and more natural sound in M50x.

However, both of these headphones have a great sound quality. The difference in sound quality between these two headphones is not so noticeable.

As these headphones are neutral sounding, the even the subtle details of the audio will be heard (especially in M50x) that you fail to hear from the mass-market headphones that have extreme folding to their frequency response.

Both of these headphones deliver rich sound quality.

And bottom line?

As I told you, the M50x has a little edge over the M40x. A non-audiophile can’t really tell the difference.

Is the extra clarity worth the extra 50 bucks?

You’re the one to decide.

Comfort

Both of these headphones offer a great comfort.

The headphones can be folded and can be stored compactly in the leather bag provided.

But the thing you need to note is that these headphones are not super-portable. Most of the people who buy any of these will mostly use it indoors.

Another difference is in terms of ear cups swiveling.

The M40x offers 90 degrees and the M50x offers 180 degrees of ear cup swiveling. This will not be a deal breaker for M40x.

Earpads and headband in both of these headphones have a soft leather finish.

But the M40x have slightly softer pads, making it a little bit more comfortable however you do need to note that the earpads on M50x do get softer over time.

The earpads in both of these are of high quality and enable you to wear these on for hours.

Sounds great!

The earpads are replaceable and available easily on the internet even by third party manufacturers as these are quite popular headphones.

The headphones are a little bit tight to wear for the large head, but it will be comfortable after some hours of wearing it.